There are a few build around cards or archetypes that are on my radar, but, for one reason or another, are not currently in the cube.

• Wildfire: This one hurt. I really like the card Wildfire. It does a lot of interested things that are unusual in the era of Modern Magic Design. And that's part of the reason it's getting cut. Wildfire decks are a style of Magic that Wizards just doesn't support anymore. I don't mind being at odds with Wizards, but sooner or later, I've had to admit that the support for all the other deck styles in this cube have surpassed Wildfire. It's a tough deck to bring together and then, when you do, it just doesn't hum like the rest of the cube does. It's fine. It's not terrible. It might come back someday. But for now, I mourn the passing of one of scorched earth Magic.
• Reanimator: Reanimator violates the spirit of "Fair Magic" instead living on the "Mostly" clause. I'm okay with it existing in this environment because it's high risk/high reward and it doesn't completely shut down any kind of back and forth gameplay with most of the available reanimate targets. This archetype was in the original iteration of the cube, but it never ended up coming together properly. People either fought over some of the key pieces or they just didn't get enough of them to pull the deck together. I cut it to make room for other things, but now that Entomb has a little redundancy via Unmarked Grave, I might consider bringing it back.
• Splinter Twin combo: I cut this because I knew it was very powerful and wanted room to test some other things that I was less sure of. Having put some distance between myself and the combo, I'm happy to leave it sidelined for awhile. The problem it presents is that it narrows the entire game down to one moment. When someone moves to go off: Do you have the removal or not? If you do, great, you've moved a little bit ahead. If you don't? Well, then nothing either of you have done for the entire game matters anymore.
• Naya Persist Combo: Selesnya and Boros are often cited as the two most one-note color combinations in cube. So, I'm looking into just mashing them all together and letting Naya be a big player in the combo game. Good-Fortune Unicorn, Metallic Mimic, and Rhythm of the Wild team up to endlessly loop Persist creatures such as Kitchen Finks and Murderous Redcap(or Woodfall Primus if you're feeling frisky) when combined with a free sacrifice outlet such as Goblin Bombardment, Greater Gargadon, and even Carrion Feeder if you'd prefer a black splash. Some of the individual combo cards are a bit weak on their own, but this should hopefully be offset by the deck's ability to function as a midrange beatdown deck when the combo doesn't show up. I'm also considering adding in Druid combo in the future. Devoted Druid+Vizier of Remedies gives infinite mana to pour into Walking Ballista, Finale of Devastation, or Rhonas the Indomitable.
• [WiP] Big Red Cheater. One of the chief complaints I've come across in cube is that certain colors are one-note. Red, for instance, is often just seen as the hyper-aggro color. I've done a couple things to try and change this up, but one that I'm not sure there's space for at the moment is to flesh out the promise that Sneak Attack offers. Through the Breach and Purphoros, Bronze-Blooded offer redundant effects, complete with a one-use, self-sacrifice clause. Ilharg, the Raze-Boar is a slower, but less all-in version of the effect. Even Fires of Invention offers Red a way to do more than beat people to death.

Cards Intentionally Excluded

• Teferi, Time Raveler: While I may not hate this card like so many others do, I also don't hold any affection for it. It's a sledgehammer designed to shatter an entire axis the game works on while generating card advantage and sitting in the colors best suited to protect him. Not particularly interesting, not particularly fun, and just not worth the fuss for me.
• Oko, Thief of Crowns: Just busted. This card does too much for too little and does so while racking up an astonishingly high loyalty level. If you ever untap with Oko, you're probably favored to win. This goes doubly for a Cube designed largely around fair and interactive Magic. Oko's major weakness of being a 3-mana do-nothing against linear combo decks disappears when those decks don't really exist.
• True-Name Nemesis: This card just kinda sucks to play against. It's a removal check card that requires a fairly specific type of removal spell. Those kinds of spells are present in this cube, but I don't want to add more and require people to have them. Adding this card would probably cause more feel bads than anything fun. Baby True-Name falls into this category as well.
• Anything involving Monarch or Initiative: These are fine mechanics in a Multiplayer setting and do a good thing in EDH where they encourage violence, but that does not translate to 1v1 Magic appropriately. I don't hate them, I just don't think they do what I want my cube to do.
• Universes Beyond: I started off going with the D.A.R.E. approach of "Just say no" because they made my brain feel weird dissonance. I've softened my stance somewhat with cards like Reprieve and Stern Scolding having effects I really dig and flavor that's subtle enough not to make my brain twitchy. We'll see how these go.